My understanding is that .. is 0-Many args and * is one arg of any name. Is this correct?
Does aspectj support syntax like args(..,myArg,..)?
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var-arg can only be the last argument (at the end) in Java. – Shark Sep 06 '12 at 15:12
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It would be very difficult/impossible for the compiler/interpreter to know which argument passed was actually `myArg` in your case. – Mike Park Sep 06 '12 at 15:14
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This is from AspectJ site: http://www.eclipse.org/aspectj/doc/next/progguide/semantics-pointcuts.html
* represents any number of characters except "."
.. represents any number of characters including any number of "."
Update From AspectJ in Action - for method signatures:
In method signatures, the wildcard .. is used to denote any type and number of arguments taken by a method
* specifies a single argument
Biju Kunjummen
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but also this : "If it is the "*" wildcard, then any argument will match, and if it is the special wildcard "..", then any number of arguments will match" – MikePatel Sep 06 '12 at 16:20
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1Yes, you are right, I have updated the answer accordingly for method signatures also. AspectJ does not support `(.., myarg, ..)`, not sure why though. – Biju Kunjummen Sep 06 '12 at 17:05
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Others have answered part of the question before me, so I will only amend:
.., bla, .. does not work because if you bind parameter bla to a variable, there might be several matching combinations in case a matching type occurs multiple times in the parameter list. Example:
void foo(int a, String b, String c, File d)
Now what should happen if the advice is:
before(String bla) : call(void foo(.., bla, ..)) && args(bla)
Should bla be bound to the String value of b or c?
kriegaex
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